ABSTRACT
Detection of Chlamydia pneumoniae [C. pneumoniae] in atherosclerotic vascular tissue to assess their role in atherogenesis, and also the choice of the best methodology for detection. Immunohistochemistry staining [IHC] for vascular tissue specimens were done on 34 atherosclerotic vascular tissues and 54 normal vascular tissues as controls [34 internal control specimens and 20 external control specimens from healthy individuals]. Using 2 monoclonal antibodies: the species specific and the Chlamydia genus-specific antibody. Three PCR assays are used for detection of C. pneumoniae DNA: Single-step PCR with different DNA polymerases enzymes, the nested PCR, and real-time quantitative PCR. C. pneumoniae DNA was detected in 58. 8% of atherosclerotic vascular tissues by single-step PCR which used Tag DNA polymerase and detection by hybridization with specific probe, no detection by other methods and also no detection in healthy vascular tissues. C. pneumoniae DNA was detected in atherosclerotic vascular tissues and no detection in healthy vascular tissues indicating that C. pneumoniae is playing a role in atherogenesis. Detection of C. pneumoniae is method dependent, so, the choice of assay I is of major importance when evaluating a relationship between C. pneumoniae and atherosclerosis